Malicious PDF — malware analysis report

Static analysis result for SHA-256 49210a006c428735…

MALICIOUS

PDF

72.2 KB Created: 2021-03-19 09:56:56 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: a09f82470bb1244ea248045dec31a035 SHA-1: b230593d0d4b84f378d198ec750b9d2cffbe2a6e SHA-256: 49210a006c4287354221fc13521a21a814da5aae90f85f096d29839526a92c64
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, suggesting it functions as a link farm, potentially for SEO manipulation or to distribute further malicious content. The primary external URL observed is https://midufefew.ru/wix?keyword=asa+commercial+oral+exam+guide.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://midufefew.ru/wix?keyword=asa+commercial+oral+exam+guide PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4415526/normal_604f69bf2aa63.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446151/normal_60291d7046005.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450721/normal_60080bd71a2bc.pdfIn PDF document text
    • http://lienforkid.com/57963324548xb1ay.pdfIn PDF document text
    • http://activa-fb.com/how_do_you_fix_a_bostitch_electric_stapleruqswq.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/biwuwukesazef/doodle_god_alchemy_apk.pdfIn PDF document text
    • https://f72b89be-0fa6-41ee-8162-331329ef78ce.filesusr.com/ugd/95089d_cba113672d9449308a9a3c8d004c542e.pdf?index=trueIn PDF document text
    • https://19d8af67-ac20-4a7c-8ffd-69be953788a8.filesusr.com/ugd/578741_9ed453ef17834bc3bc0c9a0d17c4e4eb.pdf?index=trueIn PDF document text
    • https://7133fc40-0b9c-4701-b953-e7fafc934b44.filesusr.com/ugd/70a38d_cc9f95281ebc430dace571a76c98f8ef.pdf?index=trueIn PDF document text
    • https://2a983b51-2e13-4971-8c1f-a5bca3ab4353.filesusr.com/ugd/e1a791_01e5b8d720fe4c15a736cfcf22c49977.pdf?index=trueIn PDF document text
    • https://7afcd0b8-98df-42a4-afe0-9544d44c9539.filesusr.com/ugd/74e9cf_6e25ab837bd34d9fa173d9be00f4f889.pdf?index=trueIn PDF document text
    • https://b81e1767-bb0d-4562-9f98-cfef66859bb1.filesusr.com/ugd/b48b60_252834a898d94b55a19a2128f14dabcd.pdf?index=trueIn PDF document text
    • https://d23eb412-52e1-45ef-a32a-0c032022daee.filesusr.com/ugd/03485a_101fa972c9564396947a25cad119e3ac.pdf?index=trueIn PDF document text
    • https://8767aa75-4bd5-48c0-94ca-24e983238001.filesusr.com/ugd/debdc1_79a920b5bca54decae9d9d4793348519.pdf?index=trueIn PDF document text
    • https://4465b75e-e642-4f53-8c89-e22f0b9d4994.filesusr.com/ugd/ecd213_1f4a293e5b514ee8b3e4861e403fa493.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tarizirefevifab/74444241617.pdfIn PDF document text
    • https://80820154-e864-4b0c-832b-212b24169927.filesusr.com/ugd/c12414_f60d539ff81243deadeb31058faadfeb.pdf?index=trueIn PDF document text
    • https://15319a82-8c66-4906-b3c2-464277991f2b.filesusr.com/ugd/070acf_b7ba30a941c24b39b4647aeef5bd77c2.pdf?index=trueIn PDF document text
    • https://acfc0e76-311d-46af-9c13-f46c112eb424.filesusr.com/ugd/f90bad_749ece66a69e4c30b4d2dbc4704aaebf.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB06 5316 bytes
SHA-256: 8e5b577150de55639f859451d9124df89c8b2f134382aceb4a4be58c768a8139
font_01_sfnt_off0000ed01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED01 11296 bytes
SHA-256: 91df64de144c1ef5ab56eae5509c87b8942b77f5fc5a9ef43d9e979049929efd